Normal K ink contain carbon, that is what I can't have in my printing. I have to either take out the k cartridge, so the printer prints out a black color that is make of C M Y ink. Or I have to have a special K ink that is mixed of C M Y ink, so it will still print our c m y black with no carbon in it but I don't need to take out the cartridge.
The reason is a bit complicated to explain. I need the normal k for a special code I print later on the picture, it is the carbon that helps the device read the code. So if the picture has carbon, it effects the code, then the device won't be able to read the code.
This is what I do and what happen. I print picture first and then put the picture back and print the code on top. The code is readable on lighter color of the picture but not on dark color of the picture, because the dark color contains more k ink.
I have tried your program, it does help a bit, but not enough. I am wondering if there is any thing else might helpful? Thanks!